1. Field of the Invention
The present invention relates to a brand new structure of a USB flash disk, and especially to a USB flash disk with an upper cover for tightly covering.
2. Description of the Prior Art
A USB flash disk uses a flash memory and a Universal serial bus (USB) connector for connecting to a computer for access of data, and for carrying on one's person, it is quite convenient for use, and has been widely used by people.
A conventional USB flash disk has in its structure an exposed Universal serial bus connector on a housing having therein an electric circuit board, in order to protect the Universal serial bus connector when it is not connected with a computer; a closable upper cover is added for it. The upper cover prevents dropping of the Universal serial bus connector by tightly combining with the latter. However, such an upper cover is hard to draw for opening if the combining is too tight; and is unable to be tightly covered and thus is dropped if the combining is too loose; and after using for a long time, the tight combining will be loosened, hence a defect of inconvenience in using the upper cover often exists, thereby improvement is required.